“…Recently, several researchers have been worked on DDOS defense systems and lots of novel techniques have been put forward. In DDOS attack there are three major research areas: detection of attack [6], [23], [20], [19], [1], [2], [3], [29] filtering of attack [10], [5] and attack traceback [4]. Packet scoring is one of technique [9] "that gets some attributes from TCP and IP headers and then uses classification algorithm or statistic theorems to analyze packets".…”